Improvement in devices for securing punches to their stocks



JOHN JOHNSON. Imprdvemeht in Devices for Securing Punches to theirS'tbcks..,

No. 125,302. PatentedApril2J872',

UNITED STATES PATENT QEEIOE,

JOHN JOHNSON, OF NEW YORK, N. Y.

IMPROVEMENT IN DEVICES FOR SECURING PUNCHES TO THEIR STOCKS.

Specification forming part of Letters Patent No.125,302, dated April 2,1872.

. in g the rivetholes in boiler-plates and for other purposes.Heretofore the punches in such ma chines have been ordinarily secured intheir stocks or holders simply by friction, and to obtain sufficientsurface therefor have been of considerable length to entercorrespondingly long sockets. Forging them to fit the sockets in theirstocks or holders is a very delicate operation, and one requiringconsiderable time, and when once fitted it is a difficult matter todetach them. The object of this invention is to reduce the labor ofmanufacturing the punches, to facilitate their attachment to theirstocks and detachment therefrom; also, to render their attachmentpositive likewise, by reducing the length of the punch, to economize theamount of steel used. To this end it consists in the combination, with astock or holder transversely slotted above the punch-socket, of a punchcapable of being inserted through the stop of the holder into itssocket, said punch having its upper portion swelled or enlarged toprevent it from dropping through the socket, and a key which fits saidslot and bears on the top of the in place.

In the accompanying drawing, Figure 1 is a perspective view of a punchstock or holder and attached punch constructed according to myinvention, and Fig. 2 is a central section of the same.

punch and retains it Similar letters of reference indicate correspondingparts in both figures.

A is the stock or holder in which the punch is secured. It is provided,as usual, with a shank, a, for its attachment to the press, and has ataper slot extending transversely through it, communicating with theunder side of which is the socket for the punch B. The upper part ofthis socket is flaring-or, in other words, ta-' pered from the topdownward. The punch B is of such length as to permit of its beinginserted into its socket in the stock through the slot therein. 0 is thekey which fits within the slot and secures the punch therein.

The punch is first inserted through the slot in the stock into thesocket provided for its reception, and is prevented from slippingthrough by means of its tapered or swelled upper portion fitting theflarin g portion of the socket. The key 0 is then inserted in the slotand driven in tight, and by bearing on the top of the punch it securesit in place, and that in a positive and rigid manner. To detach thepunch it is only necessary to remove the key, and. the punch may then bereadily taken out by the hand.

Claim.

The combination, with the socketed and transversely-slotted stock orholder A, of the punchB having an enlarged upper portion, and the key 0,substantially as and for the purpose herein set forth.

JOHN JOHNSON.

Witnesses:

FRED. HAYNES, R. E. RABEAU.

